P0778
DTC P0778: Problem in A/T Clutch Pressure Control Solenoid Valve B CircuitNOTE: Record all freeze data and review General Troubleshooting Information before you troubleshoot.
1. Disconnect A/T clutch pressure control solenoid valve B connector.
2. Measure A/T clutch pressure control solenoid valve B resistance at the solenoid valve connector terminals.
Is there about 5 Ohms?
YES - Go to step 3.
NO - Replace A/T clutch pressure control solenoid valve B.
3. Disconnect the battery negative terminal.
4. Disconnect PCM connectors B (24P) and C (22P).
5. Check for continuity between PCM connector terminals B16 and body ground, and between C8 and body ground.
Is there continuity?
YES - Repair short to ground in the wires between PCM connector terminals B16 and A/T clutch pressure control solenoid valve B, and between C8 and solenoid valve B.
NO - Go to step 6.
6. Connect the A/T clutch pressure control solenoid valve B connector.
7. Measure the resistance between PCM connector terminals B16 and C8.
Is there about 5 Ohms?
YES - Go to step 8.
NO - Repair loose terminal or open in the wires between PCM connector terminals B16 and A/T clutch pressure control solenoid valve B, and between C8 and solenoid valve B. P
8. Disconnect PCM connector A (31P).
9. Check for continuity between PCM connector terminals A23 and body ground, and between A24 and body ground.
Is there continuity?
YES - Check the terminal fit at PCM connector terminals B18 and C8. If the connections are OK, update the PCM if it does not have the latest software, or substitute a known-good PCM, then recheck. If the symptom/indication goes away with a known-good PCM, replace the original PCM.
NO - Repair open in the wires between PCM connector terminals A23 and ground (G101), and between A24 and ground (G101), and repair poor ground (G101).